Seung-Hyun Seo

Effective Key Management in Dynamic Wireless Sensor Networks

Recently, wireless sensor networks (WSNs) have been deployed for a wide variety of applications, including military sensing and tracking, patient status monitoring, traffic flow monitoring, where sensory devices often move between different locations. Securing data and communications requires suitable encryption key protocols. In this paper, we propose a certificateless-effective key management (CL-EKM) protocol for secure communication in dynamic WSNs characterized by node mobility. The CL-EKM supports efficient key updates when a node leaves or joins a cluster and ensures forward and backward key secrecy. The protocol also supports efficient key revocation for compromised nodes and minimizes the impact of a node compromise on the security of other communication links. A security analysis of our scheme shows that our protocol is effective in defending against various attacks. We implement CL-EKM in Contiki OS and simulate it using Cooja simulator to assess its time, energy, communication, and memory performance.

Analysis on Maliciousness for Mobile Applications

The rapid increase in smart phone users has enabled the application marketplace to grow dramatically. The black market presence has also grown rapidly, where paid applications are modified for free download. As a consequence, malicious applications are expected to spread with increasing frequency. In particular, the Android marketplace, where applications allowed to register without prior security checks, breeds further indiscreet distribution of malicious applications. This paper suggests a framework for detecting malicious behaviors in Android smart phone applications. The framework proposed here automatically collects applications from the official Android marketplace or from black markets, analyzes them and detects malicious behaviors. Furthermore, a pilot system was implemented based on the proposed framework, which can detect malicious applications, preventing users from any loss due to malware.

A Secure Communication Protocol for Drones and Smart Objects

In many envisioned drone-based applications, drones will communicate with many different smart objects, such as sensors and embedded devices. Securing such communications requires an effective and efficient encryption key establishment protocol. However, the design of such a protocol must take into account constrained resources of smart objects and the mobility of drones. In this paper, a secure communication protocol between drones and smart objects is presented. To support the required security functions, such as authenticated key agreement, non-repudiation, and user revocation, we propose an efficient Certificateless Signcryption Tag Key Encapsulation Mechanism (eCLSC-TKEM). eCLSC-TKEM reduces the time required to establish a shared key between a drone and a smart object by minimizing the computational overhead at the smart object. Also, our protocol improves drones efficiency by utilizing dual channels which allows many smart objects to concurrently execute eCLSC-TKEM. We evaluate our protocol on commercially available devices, namely AR.Drone2.0 and TelosB, by using a parking management testbed. Our experimental results show that our protocol is much more efficient than other protocols.

Encryption key management for secure communication in smart advanced metering infrastructures

Smart grid technology can improve environmental sustainability and increase the efficiency of energy management. Because of these important benefits, conventional power grid systems are being replaced with new, advanced smart grid systems utilizing Advanced Metering Infrastructures (AMIs). These smart grid systems rely on current information and communication technology (ICT) to provide enhanced services to both users and utility companies. However, the increased use of ICT makes smart grid systems vulnerable to cyber-attacks, such as spoofing, eavesdropping and man-in-the-middle attacks. A major security concern is related to secure data transmission between the smart meters and the utility. Encryption techniques are typically used for such purpose. However the deployment of encryption techniques in an AMI requires efficient and scalable approaches for managing encryption keys. In this paper, we propose an efficient encryption key management mechanism for end-to-end security in the AMI. By applying certificateless public key cryptography for smart meter key management, our approach eliminates certificate management overhead at the utility. Moreover, our mechanism is practical, because it does not require any extra hardware for authentication of the smart meters.

An Access Control Mechanism for Remote Control of Home Security System

The use of smart phones has lately grown by leaps and bounds and the role of a smart phone as a portable computer has been conspicuous. The application programs of smart phones are used in diverse areas such as business planning, banking, blogging, GPS, medical application, and home security. The diversity of such application is seen to be one of factors of the expansion of smart phone users, and to that extent, the demand of security is increasing. In particular, safety issue is more important in the control application of home security for home safety. This paper aims to control methods in the access of home security system which monitors and controls security devices, installed around houses by using smart phones. In particular, we suggest the way of dynamic delegation of authority for allowing outsiders like housekeeper to have access to the security system temporarily.

Certificateless Cryptographic Protocols for Efficient Drone-Based Smart City Applications

Smart cities aim to improve the quality of urban services and their energy efficiency by utilizing information and communication technologies. In such context, drones can be utilized to support various services, such as traffic monitoring, search/rescue, and surveillance, by communicating with many different smart objects like sensors. Securing such communications is crucial to making correct decisions and requires efficient cryptographic protocols. However, the design of such protocols must consider: 1) the mobility and the limited battery of drones and 2) the constrained resources of smart objects. In this paper, a suite of cryptographic protocols is presented to deal with three different communication scenarios: one-to-one, one-to-many, and many-to-one. For one-to-one, we propose an efficient Certificateless Signcryption Tag Key Encapsulation Mechanism (eCLSC-TKEM) that supports authenticated key agreement, non-repudiation, and user revocation. eCLSC-TKEM reduces the time required to establish a shared key between a drone and a smart object by minimizing the computational overhead at the smart object. For one-to-many, we propose a Certificateless Multi-Recipient Encryption Scheme (CL-MRES) by which a drone can efficiently send privacy-sensitive data to multiple smart objects. For many-to-one, we present a Certificateless Data Aggregation (CLDA) protocol, which allows drones to efficiently collect data from hundreds of smart objects. Also, for efficiency, we propose a dual channel strategy that allows many smart objects to concurrently execute our protocols. We evaluate eCLSC-TKEM via a smart parking management test-bed. Also, we have implemented CL-MRES and CLDA on a board with a graphics processing unit (GPU) and show their GPU-accelerated performance.

A Security Framework for a Drone Delivery Service

Delivery drones are unmanned aerial vehicles (UAV) utilized to transport packages, food, medicine, or other goods. With high demand for a prompt and efficient delivery, a drone delivery system can be an effective solution for timely deliveries and especially for emergency management. However, current delivery drone systems lack crucial security functions. Drones may have to operate in unsupervised hostile areas, and therefore be vulnerable to physical capture in addition to conventional cyber attacks. A captured drone can be analyzed by a white-box attack model in which the attacker has full control over the execution environment of cryptographic modules in static and dynamic methods including all side-channel information. In this paper, we propose and evaluate a security framework which utilizes white-box cryptography in order to protect critical data and cryptographic keys in delivery drones from white-box attacks. The experimental results show that the proposed framework is cost effective in terms of resource usage and thus is suitable even for resource-limited UAV.

Cryptanalysis of ID-based authenticated key agreement protocols from bilinear pairings (short paper)

Recently, a number of ID-based authenticated key agreement protocols from bilinear pairings have been proposed. In this paper we present security analysis of four ID-based authenticated key agreement protocols from pairings proposed in [11, 12, 7, 18]. These results demonstrate that no more ID-based authenticated key agreement protocols should be constructed with such ad-hoc methods, i.e, the formal design methodology as in [1, 2, 3, 10] should be employed in future design.

The Congestion Control Model for Unmanned Aircraft System Traffic Management

With the rapid development of unmanned aerial vehicle (UAV), they have been used in various fields such as logistics systems, agriculture system, and etc. As the consumption of UAV increases, unmanned aircraft traffic management (UTM) system has become necessary. For now, there are few studies on the UTM system for small UAVs. In this paper, we suggest congestion control model in air space by using GPS in real time. We consider the congestion in two ways such as density and traffic jam. When a UAV enters at the range of GCS, GCS figures out whether it is authorized or not. After then, GCS receives the GPS data from each UAVs. With GPS data, GCS calculates density and shows the current situation of density. In order to calculate speed and direction, we use the GPS tracking data. Depending on these data, we can predict the traffic jam. Our proposed method can help to improve navigation system of UAV and to establish UTM system.

Potential vulnerability analysis of mobile banking applications

Android with the highest market share is limiting the access of apps to Android features through permissions. This paper investigated and analyzed the present condition of use of permissions of banking apps, which handle the most sensitive data and prepared the basic data for the preparation of countermeasures by analyzing its potential risks.